Revert "make enum santizer fatal"

This reverts commit 166dbd3.

Reason for revert: illegal is not advanced, docs

Original change's description:
> make enum santizer fatal
> 
> This enum sanitizer checks that all the values of the enum we use fall
> within the range of the enumerated values.
> 
> The main thing this helps point out is that the size of enum types in
> C++ need only be large enough to hold the largest declared value; larger
> values are undefined.  In practice, most enums are implemented as ints
> for compatibility with C, so while this hasn't pointed out anything
> egregiously broken, the sanitizer has found a couple possibly dangerous
> situations in our codebase.
> 
> For most types using values outside the enum range, we can just
> explicitly size them to int.  This makes their de facto size de jure.
> 
> But we need to actually make GrBlendEquation and GrBlendCoeff not store
> values outside their enumerated range.  They're packed into bitfields
> that really can't represent those (negative) values.  So for these I've
> added new kIllegal values to the enums, forcing us to deal with our
> once-silent illegal values a bit more explicitly.
> 
> Change-Id: Ib617694cf1aaa83ae99289e9e760f49cb6393a2f
> Reviewed-on: https://skia-review.googlesource.com/c/168484
> Reviewed-by: Brian Osman <brianosman@google.com>

TBR=mtklein@chromium.org,mtklein@google.com,brianosman@google.com

Change-Id: I691c08092340a6273e442c0f098b844f7d0363ba
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/c/168581
Reviewed-by: Mike Klein <mtklein@google.com>
Commit-Queue: Mike Klein <mtklein@google.com>

gn/BUILD.gn

@@ -237,7 +237,7 @@ config("default") {
 
       # A whitelist of checks we can't yet pass.
       if (fyi_sanitize == "" && !is_android) {
-        fyi_sanitizers = "float-divide-by-zero"
+        fyi_sanitizers = "enum,float-divide-by-zero"
       }
 
       if (is_android) {

include/core/SkBlurTypes.h

@@ -10,7 +10,7 @@
 
 #include "SkTypes.h"
 
-enum SkBlurStyle : int {
+enum SkBlurStyle {
     kNormal_SkBlurStyle,  //!< fuzzy inside and outside
     kSolid_SkBlurStyle,   //!< solid inside, fuzzy outside
     kOuter_SkBlurStyle,   //!< nothing inside, fuzzy outside

include/core/SkPath.h

@@ -63,7 +63,7 @@ class SK_API SkPath {
         kCW_Direction travel clockwise; the same added with kCCW_Direction
         travel counterclockwise.
     */
-    enum Direction : int {
+    enum Direction {
         kCW_Direction,  //!< contour travels clockwise
         kCCW_Direction, //!< contour travels counterclockwise
     };

include/gpu/GrBlend.h

@@ -37,10 +37,8 @@ enum GrBlendEquation {
     kHSLColor_GrBlendEquation,
     kHSLLuminosity_GrBlendEquation,
 
-    kIllegal_GrBlendEquation,
-
     kFirstAdvancedGrBlendEquation = kScreen_GrBlendEquation,
-    kLast_GrBlendEquation = kIllegal_GrBlendEquation,
+    kLast_GrBlendEquation = kHSLLuminosity_GrBlendEquation
 };
 
 static const int kGrBlendEquationCnt = kLast_GrBlendEquation + 1;
@@ -69,9 +67,7 @@ enum GrBlendCoeff {
     kS2A_GrBlendCoeff,
     kIS2A_GrBlendCoeff,
 
-    kIllegal_GrBlendCoeff,
-
-    kLast_GrBlendCoeff = kIllegal_GrBlendCoeff,
+    kLast_GrBlendCoeff = kIS2A_GrBlendCoeff
 };
 
 static const int kGrBlendCoeffCnt = kLast_GrBlendCoeff + 1;

include/gpu/GrTypes.h

@@ -227,7 +227,7 @@ enum class GrMipMapped : bool {
  * GPU SkImage and SkSurfaces can be stored such that (0, 0) in texture space may correspond to
  * either the top-left or bottom-left content pixel.
  */
-enum GrSurfaceOrigin : int {
+enum GrSurfaceOrigin {
     kTopLeft_GrSurfaceOrigin,
     kBottomLeft_GrSurfaceOrigin,
 };

include/private/GrTypesPriv.h

@@ -384,7 +384,7 @@ GR_MAKE_BITFIELD_OPS(GrShaderFlags);
  * vary the internal precision based on the qualifiers. These currently only apply to float types (
  * including float vectors and matrices).
  */
-enum GrSLPrecision : int {
+enum GrSLPrecision {
     kLow_GrSLPrecision,
     kMedium_GrSLPrecision,
     kHigh_GrSLPrecision,

src/core/SkPathPriv.h

@@ -18,7 +18,7 @@ class SkPathPriv {
     static const int kPathRefGenIDBitCnt = 32;
 #endif
 
-    enum FirstDirection : int {
+    enum FirstDirection {
         kCW_FirstDirection,         // == SkPath::kCW_Direction
         kCCW_FirstDirection,        // == SkPath::kCCW_Direction
         kUnknown_FirstDirection,

src/gpu/GrXferProcessor.cpp

@@ -99,9 +99,6 @@ static const char* equation_string(GrBlendEquation eq) {
             return "hsl_color";
         case kHSLLuminosity_GrBlendEquation:
             return "hsl_luminosity";
-        case kIllegal_GrBlendEquation:
-            SkASSERT(false);
-            return "<illegal>";
     };
     return "";
 }
@@ -144,9 +141,6 @@ static const char* coeff_string(GrBlendCoeff coeff) {
             return "src2_alpha";
         case kIS2A_GrBlendCoeff:
             return "inv_src2_alpha";
-        case kIllegal_GrBlendCoeff:
-            SkASSERT(false);
-            return "<illegal>";
     }
     return "";
 }

src/gpu/effects/GrCustomXfermode.cpp

@@ -46,10 +46,7 @@ static constexpr GrBlendEquation hw_blend_equation(SkBlendMode mode) {
     GR_STATIC_ASSERT(kHSLSaturation_GrBlendEquation == (int)SkBlendMode::kSaturation + EQ_OFFSET);
     GR_STATIC_ASSERT(kHSLColor_GrBlendEquation == (int)SkBlendMode::kColor + EQ_OFFSET);
     GR_STATIC_ASSERT(kHSLLuminosity_GrBlendEquation == (int)SkBlendMode::kLuminosity + EQ_OFFSET);
-
-    // There's an illegal GrBlendEquation that corresponds to no SkBlendMode, hence the extra +1.
-    GR_STATIC_ASSERT(kGrBlendEquationCnt == (int)SkBlendMode::kLastMode + 1 + 1 + EQ_OFFSET);
-
+    GR_STATIC_ASSERT(kGrBlendEquationCnt == (int)SkBlendMode::kLastMode + 1 + EQ_OFFSET);
     return static_cast<GrBlendEquation>((int)mode + EQ_OFFSET);
 #undef EQ_OFFSET
 }
@@ -82,15 +79,15 @@ class CustomXP : public GrXferProcessor {
     CustomXP(bool hasMixedSamples, SkBlendMode mode, GrProcessorAnalysisCoverage coverage)
             : INHERITED(kCustomXP_ClassID, true, hasMixedSamples, coverage)
             , fMode(mode)
-            , fHWBlendEquation(kIllegal_GrBlendEquation) {
+            , fHWBlendEquation(static_cast<GrBlendEquation>(-1)) {
     }
 
     const char* name() const override { return "Custom Xfermode"; }
 
     GrGLSLXferProcessor* createGLSLInstance() const override;
 
     SkBlendMode mode() const { return fMode; }
-    bool hasHWBlendEquation() const { return kIllegal_GrBlendEquation != fHWBlendEquation; }
+    bool hasHWBlendEquation() const { return -1 != static_cast<int>(fHWBlendEquation); }
 
     GrBlendEquation hwBlendEquation() const {
         SkASSERT(this->hasHWBlendEquation());

src/gpu/gl/GrGLGpu.cpp

@@ -78,10 +78,7 @@ static const GrGLenum gXfermodeEquation2Blend[] = {
     GR_GL_HSL_HUE,
     GR_GL_HSL_SATURATION,
     GR_GL_HSL_COLOR,
-    GR_GL_HSL_LUMINOSITY,
-
-    // Illegal... needs to map to something.
-    GR_GL_FUNC_ADD,
+    GR_GL_HSL_LUMINOSITY
 };
 GR_STATIC_ASSERT(0 == kAdd_GrBlendEquation);
 GR_STATIC_ASSERT(1 == kSubtract_GrBlendEquation);
@@ -124,9 +121,6 @@ static const GrGLenum gXfermodeCoeff2Blend[] = {
     GR_GL_ONE_MINUS_SRC1_COLOR,
     GR_GL_SRC1_ALPHA,
     GR_GL_ONE_MINUS_SRC1_ALPHA,
-
-    // Illegal... needs to map to something.
-    GR_GL_ZERO,
 };
 
 bool GrGLGpu::BlendCoeffReferencesConstant(GrBlendCoeff coeff) {
@@ -151,9 +145,6 @@ bool GrGLGpu::BlendCoeffReferencesConstant(GrBlendCoeff coeff) {
         false,
         false,
         false,
-
-        // Illegal.
-        false,
     };
     return gCoeffReferencesBlendConst[coeff];
     GR_STATIC_ASSERT(kGrBlendCoeffCnt == SK_ARRAY_COUNT(gCoeffReferencesBlendConst));

src/gpu/gl/GrGLGpu.h

@@ -566,9 +566,9 @@ class GrGLGpu final : public GrGpu, private GrMesh::SendToGpuImpl {
         TriState        fEnabled;
 
         void invalidate() {
-            fEquation = kIllegal_GrBlendEquation;
-            fSrcCoeff = kIllegal_GrBlendCoeff;
-            fDstCoeff = kIllegal_GrBlendCoeff;
+            fEquation = static_cast<GrBlendEquation>(-1);
+            fSrcCoeff = static_cast<GrBlendCoeff>(-1);
+            fDstCoeff = static_cast<GrBlendCoeff>(-1);
             fConstColorValid = false;
             fEnabled = kUnknown_TriState;
         }

src/gpu/glsl/GrGLSLFragmentShaderBuilder.cpp

@@ -53,9 +53,8 @@ static const char* specific_layout_qualifier_name(GrBlendEquation equation) {
     GR_STATIC_ASSERT(12 == kHSLSaturation_GrBlendEquation - kFirstAdvancedGrBlendEquation);
     GR_STATIC_ASSERT(13 == kHSLColor_GrBlendEquation - kFirstAdvancedGrBlendEquation);
     GR_STATIC_ASSERT(14 == kHSLLuminosity_GrBlendEquation - kFirstAdvancedGrBlendEquation);
-    // There's an illegal GrBlendEquation at the end there, hence the -1.
     GR_STATIC_ASSERT(SK_ARRAY_COUNT(kLayoutQualifierNames) ==
-                     kGrBlendEquationCnt - kFirstAdvancedGrBlendEquation - 1);
+                     kGrBlendEquationCnt - kFirstAdvancedGrBlendEquation);
 }
 
 uint8_t GrGLSLFragmentShaderBuilder::KeyForSurfaceOrigin(GrSurfaceOrigin origin) {

src/gpu/mtl/GrMtlPipelineStateBuilder.mm

@@ -227,7 +227,6 @@ static MTLBlendFactor blend_coeff_to_mtl_blend(GrBlendCoeff coeff) {
         MTLBlendFactorOneMinusSource1Color,      // kIS2C_GrBlendCoeff
         MTLBlendFactorSource1Alpha,              // kS2A_GrBlendCoeff
         MTLBlendFactorOneMinusSource1Alpha,      // kIS2A_GrBlendCoeff
-        MTLBlendFactorZero,                      // kIllegal_GrBlendCoeff
     };
     GR_STATIC_ASSERT(SK_ARRAY_COUNT(gTable) == kGrBlendCoeffCnt);
     GR_STATIC_ASSERT(0 == kZero_GrBlendCoeff);
@@ -264,7 +263,7 @@ static MTLBlendOperation blend_equation_to_mtl_blend_op(GrBlendEquation equation
     GR_STATIC_ASSERT(1 == kSubtract_GrBlendEquation);
     GR_STATIC_ASSERT(2 == kReverseSubtract_GrBlendEquation);
 
-    SkASSERT((unsigned)equation < kGrBlendEquationCnt);
+    SkASSERT((unsigned)equation < kGrBlendCoeffCnt);
     return gTable[equation];
 }
 

src/gpu/vk/GrVkPipeline.cpp

@@ -320,7 +320,7 @@ static VkBlendFactor blend_coeff_to_vk_blend(GrBlendCoeff coeff) {
         VK_BLEND_FACTOR_ONE_MINUS_SRC1_COLOR,      // kIS2C_GrBlendCoeff
         VK_BLEND_FACTOR_SRC1_ALPHA,                // kS2A_GrBlendCoeff
         VK_BLEND_FACTOR_ONE_MINUS_SRC1_ALPHA,      // kIS2A_GrBlendCoeff
-        VK_BLEND_FACTOR_ZERO,                      // kIllegal_GrBlendCoeff
+
     };
     GR_STATIC_ASSERT(SK_ARRAY_COUNT(gTable) == kGrBlendCoeffCnt);
     GR_STATIC_ASSERT(0 == kZero_GrBlendCoeff);
@@ -369,10 +369,7 @@ static VkBlendOp blend_equation_to_vk_blend_op(GrBlendEquation equation) {
         VK_BLEND_OP_HSL_HUE_EXT,
         VK_BLEND_OP_HSL_SATURATION_EXT,
         VK_BLEND_OP_HSL_COLOR_EXT,
-        VK_BLEND_OP_HSL_LUMINOSITY_EXT,
-
-        // Illegal.
-        VK_BLEND_OP_ADD,
+        VK_BLEND_OP_HSL_LUMINOSITY_EXT
     };
     GR_STATIC_ASSERT(0 == kAdd_GrBlendEquation);
     GR_STATIC_ASSERT(1 == kSubtract_GrBlendEquation);
@@ -420,9 +417,6 @@ static bool blend_coeff_refs_constant(GrBlendCoeff coeff) {
         false,
         false,
         false,
-
-        // Illegal
-        false,
     };
     return gCoeffReferencesBlendConst[coeff];
     GR_STATIC_ASSERT(kGrBlendCoeffCnt == SK_ARRAY_COUNT(gCoeffReferencesBlendConst));